Gemfile in zser-0.0.0 vs Gemfile in zser-0.0.1

@@ -1,11 +1,15 @@
 # frozen_string_literal: true
 
 source "https://rubygems.org"
+ruby RUBY_VERSION
 
 gemspec
 
 group :development, :test do
+  gem "benchmark-ips"
+  gem "guard-rspec"
   gem "rake"
   gem "rspec", "~> 3.5"
-  gem "rubocop", "0.44.1"
+  gem "rubocop", "0.48.1"
+  gem "tjson", "~> 0.5"
 end